package com.atguigu.day02;

/**
 * @ClassName ThreadOrderAccess
 * @Description 此类描述:
 * @Author dangchen
 * @DateTime 2022-09-07 18:52
 * @Version 1.0
 */

import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * 三个线程之间按顺序调用,实现A->B->C
 * 三个线程启动,要求如下:
 * AA打印5次,BB打印10次,CC打印15次
 * ......
 * 如此执行10轮
 * 1 高内聚低耦合前提下  线程  操作  资源类
 * 2 判断  干活  通知
 * 3 防止虚假唤醒 wait--while
 * 4 多线程变更标志位
 */
class ShareResource{
    private int flag = 1;//A-1 B-2 C-3
    private Lock lock = new ReentrantLock();
    private Condition condition1 = lock.newCondition();
    private Condition condition2 = lock.newCondition();
    private Condition condition3 = lock.newCondition();

    public void print5(){
        lock.lock();
        try {
            //1.判断
            while (flag != 1){
                condition1.await();
            }
            //2.干活
            for (int i = 0; i < 5; i++) {
                System.out.println(Thread.currentThread().getName()+ "\t AA");
            }
            //3.通知
            flag = 2;
            condition2.signal();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }

    public void print10(){
        lock.lock();
        try {
            //1.判断
            while (flag != 2){
                condition2.await();
            }
            //2.干活
            for (int i = 0; i < 10; i++) {
                System.out.println(Thread.currentThread().getName() + "\t BB");
            }
            //3.通知
            flag = 3;
            condition3.signal();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }

    public void print15(){
        lock.lock();
        try {
            //1.判断
            while (flag != 3){
                condition3.await();
            }
            //2.干活
            for (int i = 0; i < 15; i++) {
                System.out.println(Thread.currentThread().getName() + "\t CC");
            }
            //3.通知
            flag = 1;
            condition1.signal();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }
}
public class ThreadOrderAccess {
    public static void main(String[] args) {
        ShareResource shareResource = new ShareResource();
        new Thread(() -> {
            for (int i = 0; i < 10 ; i++) {
                shareResource.print5();
            }
        },"A").start();

        new Thread(() -> {
            for (int i = 0; i < 10; i++) {
                shareResource.print10();
            }
        },"B").start();

        new Thread(() -> {
            for (int i = 0; i < 10; i++) {
                shareResource.print15();
            }
        },"C").start();
    }
}
